Transitional-cell carcinoma of the urachal apex

LTHOUGH microscopic adenomas and cystsA may be frequently found in dissected specimens of the urachus from adults, neoplasms of this structure of sufficient size to produce clinical manifestations are uncommon.In 1931 B e g 4 reviewed the clinical and pathological features of forty-four tumors recorded in the world literature that were considered to be of urachal origin.However, he deleted ten examples representing such mesenchymal neoplasms as fibroma, fibromyxoma, leiomyoma, and sarcoma, urging that only those tumors with epithelial components compatible with that encountered in anatomical dissections or that recapitulate the embryogenesis of this structure be accepted.Although he recognized the theoretical possibility of tumors arising from the smooth muscle and fibrocytic elements of the urachus, he believed that previous examples of such lesions were most likely derived from the fibrous bands of this structure intimately attached to the adventitia of the vestigial umbilical arteries or similar components of the space of Retzius rather than the urachus per se.All of the acceptable urachal tumors were carcinomas except three designated fibroadenoma.Hayes and SegaP reviewed the urachal carcinomas recorded up to 1945 and found only forty-four.Since then, several case reports have a p peared,21 6, 1-10*1** 1 6 and recently Mostofi, Thomson, and Dean" considered sixteen of forty-four examples of mucinous adenocarcinoma of the urinary bladder as probably urachal in origin, bringing the total number of cases to approximately seventy.Almost all recorded examples of urachal carcinoma have originated in the distal 1 cm. of this structure, which penetrates the vesical wall.There are only three instances'.6s 11 in which such a neoplasm has apparently been derived from urachal rests located between the apex of the urachus and the umbilicus, al-From